Steve Jackson Games - Site Navigation
Home General Info Follow Us Search Illuminator Store Forums What's New Other Games Ogre GURPS Munchkin Our Games: Home

Go Back   Steve Jackson Games Forums > Roleplaying > GURPS

Reply
 
Thread Tools Display Modes
Old 04-16-2020, 11:00 AM   #1
Dewey
 
Join Date: Aug 2010
Location: New mexico
Default Plate armor thicknesses

I apologize if this has already been discussed, but what are the approximate thicknesses for the various levels of plate armor from Low Tech? For example would Light Plate be equivalent to, say, 20 gauge steel, Medium Plate to 16 gauge, and Heavy Plate to 12 gauge? I realize that medieval steel was a lot worse than modern homogeneous steel, but I'd like a ballpark to figure out what DR values modern reproduction armor would have for a post-apocalyptic game I'm planning.
Dewey is offline   Reply With Quote
Old 04-16-2020, 11:18 AM   #2
AlexanderHowl
 
Join Date: Feb 2016
Default Re: Plate armor thicknesses

This really depends on the sheer strength and hardness of the steel. Steels can vary by a factor of 10 in sheer strength and by a factor of two in hardness. This is one of the reasons why modern plate armor can be so much better than historical plate armor.

In general, historical plate armor is made from soft steel and cushioned by a layer of cloth padding for comfort and safety (which also prevents the sweat of the wearer from corroding the armor). Light plate would probably be 1/8" thick, medium plate 3/16" thick, and heavy plate 1/4" thick. This does not include the thickness of the cloth padding.
AlexanderHowl is offline   Reply With Quote
Old 04-16-2020, 11:42 AM   #3
Anthony
 
Join Date: Feb 2005
Location: Berkeley, CA
Default Re: Plate armor thicknesses

Modern reenactment armor steel isn't better quality than historical armor, it's just much much cheaper.
__________________
My GURPS site and Blog.
Anthony is offline   Reply With Quote
Old 04-16-2020, 12:02 PM   #4
DouglasCole
Doctor of GURPS Ballistics
 
DouglasCole's Avatar
 
Join Date: Sep 2004
Location: Lakeville, MN
Default Re: Plate armor thicknesses

Quote:
Originally Posted by Dewey View Post
I apologize if this has already been discussed, but what are the approximate thicknesses for the various levels of plate armor from Low Tech? For example would Light Plate be equivalent to, say, 20 gauge steel, Medium Plate to 16 gauge, and Heavy Plate to 12 gauge? I realize that medieval steel was a lot worse than modern homogeneous steel, but I'd like a ballpark to figure out what DR values modern reproduction armor would have for a post-apocalyptic game I'm planning.
Modern homogenized steel used to calibrate bullet stuff (Rolled Homogeneous Armor) is ballparked at DR 70 per inch, which gives approximately DR 2.75 per mm.
__________________
My blog:Gaming Ballistic, LLC
My Store: Gaming Ballistic on Shopify
My Patreon: Gaming Ballistic on Patreon
DouglasCole is offline   Reply With Quote
Old 04-16-2020, 12:11 PM   #5
StevenH
 
Join Date: Feb 2008
Location: Portland, Oregon
Default Re: Plate armor thicknesses

Here is some info from a Quora question asking the same thing:
https://www.quora.com/How-thick-was-...l-and-the-skin


And here, from MyArmoury.com: http://myarmoury.com/talk/viewtopic.php?t=9475


Thicknesses ranged from 1-3mm on helmets, 1.5-2mm on the thickest parts of the breastplates (the front, tapering a bit on the sides).


Armor was built to protect; plate armor was good enough that historically shield use started to disappear, both because it wasn't as necessary and because if you are fighting another plate armor wearer a sword isn't going to be the best weapon to use--a poleaxe is. Swords are sidearms, not the primary weapon. You don't cut through armor. You bypass it by going for slits/chinks, hence estocs, rondels, and half-swording. Or flipping the sword around and doing a murder stroke, if you don't have a mace or warhammer handy.
__________________
Warmest regards,

StevenH

My current worldbuilding project. You can find the Adventure Logs of the campaign here. I try to write them up as narrative prose, with illustrations. As such, they are "embellished" accounts of the play sessions.


Link of the moment: Bestiary of Plants. In a world of mana, plants evolved to use it as an energy source.



It is also the new home of the Alaconius Lectures, a series of essays about the various Colleges of Spells.
StevenH is offline   Reply With Quote
Old 04-16-2020, 12:35 PM   #6
Varyon
 
Join Date: Jun 2013
Default Re: Plate armor thicknesses

Pyramid #3/52's armor design article may be of use here, as might the follow-up article from Pyramid #3/85. Cheap iron is DR 52/inch, good iron is DR 68/inch, good steel (and RHA) is DR 70/inch, ~TL4 hardened steel is DR 81/inch (but can't be made very thick until ~TL6), and TL 8 ultra-strength steel is DR 116/inch. That's all armor steel, of course. Mild steel isn't on the list; a quick bit of Googling indicates it has ~80% of the protective value of RHA; assuming this works out to 80% of the DR, that's DR 56/inch (assuming the same density; RHA is apparently a bit denser than mild steel, but I can't find a density value for it with a quick search), only a bit better than cheap iron, and probably a W (if using the articles for armor design) of 0.725. Armor used on film sets and the like I think is often made of aluminum alloy (to reduce weight), which is only around DR 35/inch for armor-grade alloys.

The above should give you some decent ballparks. For example, 16-gauge (1/16") plate armor would give DR 2.2 if made of aluminum alloy, DR 3.5 if made of mild steel, DR 4.4 if made of RHA, DR 5 if made of TL 6 hardened steel, or DR 7.25 if made of TL 8 ultra-strength steel.
__________________
GURPS Overhaul
Varyon is offline   Reply With Quote
Old 04-16-2020, 02:09 PM   #7
Dewey
 
Join Date: Aug 2010
Location: New mexico
Default Re: Plate armor thicknesses

Thanks all for the excellent answers, this was a big help! Most of my experience with armor has been with the SCA, which I know doesn't necessarily give a perfect notion of how things actually were historically.
Dewey is offline   Reply With Quote
Old 04-16-2020, 04:44 PM   #8
DanHoward
 
DanHoward's Avatar
 
Join Date: Mar 2005
Location: Maitland, NSW, Australia
Default Re: Plate armor thicknesses

Quote:
Originally Posted by StevenH View Post
Thicknesses ranged from 1-3mm on helmets, 1.5-2mm on the thickest parts of the breastplates (the front, tapering a bit on the sides).
The lightest extant breastplates are 1-1.5mm thick on the front. The heaviest are 8-9mm on the front.
__________________
Compact Castles gives the gamer an instant portfolio of genuine, real-world castle floorplans to use in any historical, low-tech, or fantasy game setting.
DanHoward is online now   Reply With Quote
Old 04-16-2020, 09:20 PM   #9
Keampe
 
Join Date: Apr 2020
Default Re: Plate armor thicknesses

8-9mm? Which extant example is this? Not even a breastplate with plastron is that thick - at least I haven't seen one. Could you be referring to some sort of jousting armor? Even then.....

As to SCA armour it tends to be thicker than it's medieval counterparts when made of steel. It's designed to keep you safe from weekly fight practices and weekly event fights, with the modern sensibility of not considering a broken finger or some such acceptable during practice. Actual medieval armour tends to be quite thin - the 1-1.5mm on the front with a plastron maybe doubling that. It would likely not be used in practice, just saved for battle or parade.

- Shane
Keampe is offline   Reply With Quote
Old 04-16-2020, 09:56 PM   #10
Say, it isn't that bad!
 
Join Date: Dec 2013
Default Re: Plate armor thicknesses

Most probably, such an example would be around the 17th-century (1600s), when gunpowder and pike were the king of the battlefield, and a very heavy breastplate might protect you from a shot or three past fifty yards.
Say, it isn't that bad! is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Fnords are Off
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -6. The time now is 10:53 PM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2024, vBulletin Solutions, Inc.